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["Sebastien Loriot (GeometryFactory)" <>]

Constrained_triangulation_plus_2<Tr> inherits from Tr which in the end
inherits from Triangulation_2 [1] and Constrained_triangulation_2 [2] .

You can thus iterator over all edges, check if it is constrained and
get the incident faces.

for( Finite_edges_iterator eit=cdt.finite_edges_begin(),
                           eit_end=cdt.finite_edges_end();
                           eit!=eit_end;
                           ++eit)
{
  if ( cdt.is_constrained(*eit) )
  {
    Face face1 = eit->first;
    Face face2 = eit->first->neighbor( eit->second);
  }
}

Sebastien.

[1] 
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Triangulation_2_ref/Class_Constrained_triangulation_2.html

[2] 
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Triangulation_2_ref/Class_Triangulation_2.html

On 10/18/2012 06:00 PM, gzp wrote:
> Hi,
>
> In one of my project I have a Constrained_triangulation_plus_2. I can
> extract all kind of information. Add and fill the user defined triangle
> information as required, I jut simple cannot find a way to find the (2)
> neighboring faces of a (sub)constraint.
> I can iterate over the subdivided edges using the Subconstraint_iterator,
> but how can I find the associated faces? In theory there can be at most 2
> such faces (or infinite_faces), but how to find them ?
>
> I mean something like this:
>
> std::vector<MYEdges>  E;
>
> for( Subconstraint_iterator scit = cdt.subconstraints_begin(); scit !=
> cdt.subconstraints_end(); ++scit) {
>    Vertex_handle v1 = scit->first.first;
>    Vertex_handle v2 = scit->first.second;
>    Face_handle left = cdt.find_face(v1,v2);
>    Face_handle right = cdt.find_face(v2,v1);
>
>    E.push_back( MyEdge( v1,v2, left->info().data, right->info().data ) );
> }
>
>
> Thanks, gzp
>
>
>
>
> --
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> http://cgal-discuss.949826.n4.nabble.com/How-to-find-faces-of-a-sub-constrained-in-Constrained-triangulation-plus-2-tp4656050.html
> Sent from the cgal-discuss mailing list archive at Nabble.com.